I just want to give a shout out to some great artists I've worked with over the last few years...
Jason Braun: http://www.jasonbraun.com/index.html
Andy Taylor: http://www.elfwood.com/art/a/t/atomtaylor/atomtaylor.html
Jeremy Pea: http://malcadon.deviantart.com/
Peter Mullen: http://www.freewebs.com/mullenart/art.htm
...and finally an up and coming star of old-school art:
Steve Zieser: http://curmudgeonsdragons.blogspot.com/
These guys have been great to work with! I can boast that each artist I've hired has been reliable, friendly, and 100% professional. I think people sometimes underestimate the effect art has on a product. Many people make choices about which game system to use based solely on the way it is represented by cover art or interior art. Art can grant a perceived "feel" to a game, even granting interpretation to text that otherwise wouldn't be.